Messages

1

Chronos User Discussion / DNG profile to closely match Chronos 1.4 LCD screen?

« on: February 26, 2025, 04:14:46 PM »

One issue I've always had with darker scenes shot with my Chronos 1.4 is that frames appear significantly brighter and less grainy on the camera's LCD than when I open them on a PC monitor.  Increasing the brightness Camera RAW to match what is on the camera's LCD always brings out a massive amount of grain.   Is there a RAW processing workflow that can correct for this? 

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General high-speed discussion / Re: Anyone manning the forum?

« on: February 17, 2025, 01:04:36 AM »

I'm not familiar with the back-end options on this forum, but enabling a setting requiring moderator approval of the first couple of posts of new accounts is usually enough, if it's available.  There also might be some sort of commonality or pattern with them in terms of the email addresses or IPs that could be auto-blocked or accounts auto-denied.

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General high-speed discussion / Anyone manning the forum?

« on: February 15, 2025, 06:02:30 PM »

Nothing but AI bot posts in the past month, possibly some new user filtering is in order?

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Chronos User Discussion / Anyone experiencing hard drive filesystem issues?

« on: November 06, 2024, 09:02:54 PM »

I'm curious if anyone here has experienced corrupted hard drive filesystem (file/folder tables) issues after copying/processing image sequences from the Chronos.  I have shot exclusively DNG sequences on my 1.4. My workflow is:

1.) Copy the captured files/folders from the camera's SD card to an external hard drive (using either an internal or external card reader)
2.) Apply camera raw edits in Adobe Bridge
3.) Export DNG to JPG or TIFF sequence using Photoshop's image processor
4.) Debanding operation with Topaz that creates another jpg/tiff sequence in a separate folder
5.) Upscale operation that creates yet another jpg sequence.

Over the course of several years on two different Windows 10/11 computers with multiple external hard drives of various brands, I have been seeing file system corruptions very close in time to (or immediately after) this workflow, sometimes as soon as right after the initial file copy from the Chronos' SD card (as in when taking the initial look at the copied files in Adobe Bridge).  As in, I view one folder, then another, then go back to the first one, and the first folder is just *gone*.  Sometimes the entire *batch* of newly copied folders vanishes.   From Bridge, File Explorer, everything.  A couple of times it has happened right after I tried renaming one of the copied folders.

These corruptions result in entire directories and files vanishing from the disk.  Occasionally everything saved after the date of the corrupting event (including unrelated folders/files like html web pages and other photo/video files) will be either gone or the files un-openable.  A chkdsk scan has recovered everything in a few cases, but on several occasions the data was lost.   Some of the chkdsk scans have failed with an error “stale information about crosslinks”.  In all cases, the corruption did not impact any pre-existing files or folders.

I have been troubleshooting this issue for years now and have never been able to zero in on a cause, but there is a very strong correlation with copying/processing files from the Chronos.  I'm not saying it is definitely related to the camera, it could be something in the workflow.  I'm just curious if other Chronos users have seen this.

5

Chronos User Discussion / Re: Spare Battery with charger for chronos 2.1 hd

« on: February 04, 2024, 06:18:39 PM »

I've run my 1.4 for about an hour plugged into an inverter powered by a car jumper pack, with more battery life to spare.  Cheap, and it works.  I regularly run my 1.4 for 6-10 hours at a time plugged into an inverter in my car. 

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Chronos User Discussion / Re: Fitting the Micro Four Thirds Mount

« on: June 22, 2023, 10:12:50 AM »

I've been shooting using a C-to-EF adapter on my Chronos 1.4 since March of 2019 with great difficultly.  No C to EF adapter on the market is stable enough to shoot with the weight of a the 11-16mm EF lens.  The connection continually works loose, causing the backfocus distance to change which makes the lens go out of focus and require resetting the focus.  This happens nearly every time the camera is picked up, and I have countless shots ruined by being out of focus due to this issue.   I eventually bought a rail system to provide more support to the entire setup, but even this was not enough to stop movement of the lens on the adapter.

The MFT mount appears to have completely fixed this problem. I have a native MFT wide-angle lens and an MFT-to-EF adapter using the same 11-16mm lens, both are rock solid now and I don't need to keep using the unwieldy rail system.

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Chronos User Discussion / Re: Effective focal lengths/f-stops for lenses with various Chronos mounts

« on: June 07, 2023, 12:12:37 AM »

Thank you, that makes perfect sense!  I'm likely going to go with some sort of a fisheye MFT lens, as it simplifies the setup and gives me a little wider frame than what I have with the 11mm lens.

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Chronos User Discussion / Re: Effective focal lengths/f-stops for lenses with various Chronos mounts

« on: June 06, 2023, 11:23:13 PM »

I'm currently using a Tokina 11-16mm on the Chronos 1.4 using an EF to C mount adapter.  The field of view on the Chronos at 11mm and the full 1280 width setting (IE at 1280x720 at 1,502fps) is considerably more narrow - possibly two to three times more so -  than the equivalent field of view on my Canon EF DSLR.  I suppose then the question would be what would the EF crop sensor conversion factor to the Chronos be?

I'm familiar that the field of view narrows as you reduce the frame size to increase the FPS. The baseline I'd be looking at for a conversion factor would be at the full 1280 width on the Chronos 1.4 as it compares to the frame on a full-frame or crop-sensor DSLR.

I decided to get the MFT mount due to my ongoing problems with the physical stability of the c-mount adapter.

I suppose the bulk of my confusion comes from never using an MFT camera or lens before.   I know about the crop factor as it pertains to using a full-frame lens on a crop sensor camera, but many sources say that MFT lenses on a MFT mount all have crop factors of 2X.

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Chronos User Discussion / Effective focal lengths/f-stops for lenses with various Chronos mounts

« on: June 06, 2023, 10:28:03 PM »

Is there a nice shorthand way to calculate effective focal length and f-stop for lenses mounted on the Chronos using adapters?

For instance, I know that using the EF-to-C mount adapter increases the lenses' effective focal length (making it less wide) and raises the effective f-stop (making it slower).  Presumably, so does the new MFT mount due to increasing the distance from the sensor to the lens.  Even more so if using an EF-to-MFT adapter stacked onto the MFT mount.

I was hoping there would be simple conversion factors/ formulas you could use to predict how any given lens will end up when using various adapters on the Chronos.

For example using a 9mm F2.8 EF-mount fisheye with an EF-to-MFT adapter on the MFT mount might end up as a factor of 2, resulting in an effective 18mm F5.6 lens.  I was hoping there would be a nice easy multiplier you could use like that.

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Chronos User Discussion / Re: Micro Four Thirds Mount for Chronos 1.4 and 2.1-HD cameras NOW AVAILABLE!

« on: June 06, 2023, 09:58:40 PM »

Any EF lens users with this new mount, what EF to MFT adapter did you end up using?  Most of the ones I see available have electrical contacts to pass through the autofocus and aperture control, which are unnecessary in this application.  However, most of the ones without the electrical pass-throughs are pretty low quality with bad reviews.  I need something that works well, but don't want to spend the extra money for the ones with the electrical contacts that I don't need.  I'm also hoping to minimize the hit on effective field of view and f-stop.

I'm also open to just getting a native MFT wide-angle lens.  Currently using the Tokina 11-16mm EF mount.

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Chronos User Discussion / Re: Filming lightning

« on: April 06, 2023, 04:28:40 AM »

I do a lot of filming of lightning with the Chronos 1.4.   Keep in mind that what you are trying to capture with high speed cameras is the *leaders*, which are very dim relative to the very bright return stroke. The leader propagation is the interesting part of a lightning flash to capture in high speed, so you would expose for them rather than the bright return stroke.  This means the return stroke will almost always overexpose, but it's no big deal as it's not the part of the event that has much you can resolve at the Chronos' framerates.

Again, lightning leaders are faintly luminous and do not show up well on the Chronos unless they are relatively close (within 2 or 3 miles) or they are the brighter ones associated with a high peak current flash.   The fastest lens you can afford at its most wide-open aperture helps.   I am using an F2.8 wide angle lens, and I can capture most leaders within 3 miles distance.

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Chronos User Discussion / Re: Chronos 1.4 Footage Thread

« on: November 13, 2021, 10:35:47 AM »

Thank you!  I am using a Tokina 11-16mm, EF-to-C mount.

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Chronos User Discussion / Re: Chronos 1.4 Footage Thread

« on: October 26, 2021, 06:21:58 AM »

I started shooting above the 10k FPS mark on the 1.4 this weekend, and managed to capture two cloud-to-ground lightning strikes.  496 x 268 at 10,034 FPS.

https://www.youtube.com/watch?v=YLzrNu8Bpqk

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Chronos User Discussion / Re: Dealing with constantly-loosening EF-mount adapter

« on: August 28, 2021, 11:44:11 PM »

Update after shooting with this rig all spring and summer.   In addition to the Camvate rail system, I bought a different brand of lens adapter - a Vello (first one was the Fotodiox).   The two brands are very similar.

Sadly, even with all of the bracing from the rail system, the simple act of repeatedly setting the camera down on the passenger seat of the car over months of use was enough to start loosening things up again.    The Vello adapter screws now require re-tightening after a day or two of use, and the camera's lens mount actually has started rotating slightly.  With the wide-open aperture (and associated narrow depth of field) required to get useable exposures in outdoor daylight, these even very slight movements often require refocusing the lens - a task very difficult without very bright daytime lighting conditions.   The loose lens adapter screws often allow the lens to wobble on its axis, meaning one half of the image is in focus, the other out of focus.

I have added a zip tie to further secure the lens to the rail's y-support, but this is only a stopgap.   My next measure will be to install a tripod head in my car to perma-mount the rig, so that the lens never encounters *any* lateral force. It appears just the weight of the camera resting on its side is enough to work it loose over time.  It certainly appears that a native mount is going to be the only long-term stable solution.

Again, I usually need to set focus during the day and rely on that setting for the evening and nighttime.   Getting a good focus set in the dark, even when the camera is set to 30fps, is many times impossible.

15

Chronos User Discussion / Re: Chronos 1.4 Footage Thread

« on: August 11, 2021, 08:55:44 PM »

This year I shot lightning footage at 6,000FPS (actually 6,002 FPS at 640 x 354) on the 1.4.  Here is the highlight reel of those captures:

https://www.youtube.com/watch?v=O1yWryv9SxY